1. Field of the Invention
The present invention relates generally to the field of lighting systems. It finds particular application in conjunction with light emitting diode strips and will be described with particular reference thereto. It will be appreciated, however, that the invention is also amenable to other like applications.
2. Discussion of the Art
Channel letters are known to those skilled in the art of making commercial signs as the most attractive and expensive form of sign lettering. Briefly, channel letters usually include a plastic or metal backing having the shape of the letter to be formed. Metal channel siding, frequently formed of aluminum with a painted or otherwise finished interior and exterior surface, is attached to and sealed to the letter backing, giving depth to the letter to be formed. Electrical lighting fixtures, such as neon tubing and mounting brackets, are attached to the letter backing. Typically, a colored, translucent plastic letter face is attached to the front edge portion of the channel side material.
As discussed above, neon lighting is typically incorporated into channel lettering systems. Neon systems are very fragile and, therefore, tend to fail and/or break during manufacture, shipping or installation. Also, such lighting systems use high voltage (e.g., between about 4,000 and about 15,000 volts) electricity to excite the neon gas within the tubing. High voltage applications have been associated with deaths by electrocution and building damage due to fire. Semiconductor lighting (e.g., light emitting diodes), that overcomes most of these drawbacks, has been used for channel lettering.
One such conventional channel lettering device attaches a light emitting diode (xe2x80x9cLEDxe2x80x9d) system to a back of a channel letter such that the LED system emits light toward a translucent face at a front of the device. The LEDs are spaced at regular intervals (e.g., 2 inches) and are pressed into a socket. The socket is designed for a press-fit of a modified Super Flux (Piranha) package. The lead frames of the Piranha are bent 90 degrees to fit into the socket. The connection for the LED is similar to insulation displacement (xe2x80x9cIDCxe2x80x9d). The socket also has two (2) IDC places for a red and black wire. This system puts all of the LEDs in parallel. Furthermore, the two part power supply (Initial (120 VAC to 24 VDC) and the Secondary (24 VDC to xcx9c2.3 VDC)) have two (2) basic wiring connections. The secondary has a sense circuit, which has one (1) LED attached for determining the voltage applied to the rest of the LEDs that are attached to the second connection.
Another conventional channel lettering device attaches to a side of the channel letter and is pointed toward the backing. The diffuse surface of the channel letter walls provides a uniform appearance. Each module has a predetermined number of LEDs electrically connected in series. Furthermore, all of the modules are daisy chained together in a parallel circuit. The LEDs are mounted on an aluminum base for heat sinking purposes.
Another conventional channel lettering device uses a plurality of surface mounted LEDs with an integral connector system.
Although these conventional LED channel lettering systems overcome some of the drawbacks associated with neon systems, other shortcomings are evident. For example, the conventional LED channel lettering systems offer only limited flexibility. More specifically, the LEDs cannot be easily set into a desired shape involving significant curves or bends (e.g., wrapped around a pole or in a very small radius ( less than 3 inches). Furthermore, the LEDs cannot be easily moved from one lighting application to another.
The present invention provides a new and improved apparatus and method that overcomes the above-referenced problems and others.
An LED light engine includes an electrical conductor, a flexible, electrically insulating covering surrounding the electrical conductor, and an LED. The LED electrically contacts the electrical conductor and is mechanically secured to the insulating covering.
In accordance with one aspect of the invention, the electrical conductor includes a plurality of conductive elements.
In accordance with a more limited aspect of the invention, each of the conductive elements includes about seven (7) strands and is about 14 gauge.
In accordance with another aspect of the invention, the flexible covering surrounds and electrically insulates each of the conductive elements.
In accordance with a more limited aspect of the invention, the LED includes a plurality of electrical leads. A pair of the leads displaces the insulating covering and contacts respective ones of the conductive elements.
In accordance with an even more limited aspect of the invention, each of the electrical leads is wedge-shaped.
In accordance with another aspect of the invention, the flexible covering includes a plurality of dips positioned for aligning the leads with the conductive elements.
In accordance with another aspect of the invention, a connector is mechanically secured to the flexible insulating covering and electrically contacts the electrical conductor. The LED electrically contacts the electrical conductor and is mechanically secured to the insulating covering via the connector.
In accordance with a more limited aspect of the invention, the conductor includes a plurality of conductive elements, each of which is electrically insulated by the flexible covering from the other conductive elements. The connector includes a plurality of electrical contacts that extend through the flexible covering and electrically contact respective ones of the conductive elements. The LED is electrically connected to the electrical contacts.
In accordance with an even more limited aspect of the invention, each of the electrical contacts is V-shaped. Each of the conductive elements is positioned within an opening defined by the respective V-shaped electrical contact.
One advantage of the present invention is that it may be used with direct or indirect multi-color illumination systems including LED strip lighting systems.
Another advantage of the present invention is that it permits LEDs to be evenly spaced to provide a uniform appearance in or on an application.
Another advantage of the present invention is that it provides a substantially equal intensity to neon in the lighting system.
Another advantage of the present invention is that it provides for in-plane and out-of-plane bending of the illumination system (e.g., wrapping the illumination system around a pole).
Another advantage of the present invention is that the connector may be mounted on a wire that is set up on edge for maximum flexibility around small radius bends.
Another advantage of the present invention is that the illumination system may be spooled.
Another advantage of the present invention is that it provides for quick and easy installation of a light engine into an application.
Another advantage of the present invention is that it reduces electrical and/or fire hazards.
Another advantage of the present invention is that it reduces energy consumption.
Another advantage of the present invention is that it reduces installation and shipping breakage.
Another advantage of the present invention is that it provides for multi-colored lighting systems.
Still further advantages of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the preferred embodiments.
Another advantage of the present invention is that the connectors can be added or removed from the insulating wire.
Another advantage of the present invention is that it can be cut to any useful length.